The **LSRFSGM3362-R1** is a high-performance, integrated **FMCW (Frequency Modulated Continuous Wave) Radar Sensor Module** operating in the **24GHz ISM band**. It is primarily designed for short-range motion detection, distance measurement, and velocity sensing. Below is a breakdown of its electronic components, technical specifications, and pinout architecture. --- ### 1. Key Technical Specifications | Parameter | Specification | | :--- | :--- | | **Operating Frequency** | 24.00 GHz to 24.25 GHz | | **Detection Range** | Up to 15-20 meters (depending on target RCS) | | **Supply Voltage (VCC)** | 3.3V to 5.0V DC | | **Operating Current** | ~50mA to 80mA | | **Interface** | UART (Serial) / GPIO | | **Antenna Gain** | Integrated Microstrip Antenna (typical 5-8 dBi) | | **Beamwidth** | 80° Horizontal / 34° Vertical (approximate) | --- ### 2. Internal Electronic Architecture The module integrates several complex high-frequency components onto a single PCB: #### A. MMIC (Monolithic Microwave Integrated Circuit) The heart of the module is the 24GHz transceiver chip. It handles: * **VCO (Voltage Controlled Oscillator):** Generates the high-frequency signal. * **Power Amplifier (PA):** Boosts the signal for transmission. * **Mixer:** Combines the reflected signal with the transmitted signal to extract the "Beat Frequency" (IF signal). #### B. Integrated Microstrip Antenna The back or front of the PCB contains etched copper patterns acting as the **Transmitter (TX)** and **Receiver (RX)** antennas. This eliminates the need for external bulky antennas. #### C. Signal Processing Unit (MCU/DSP) Unlike raw radar sensors, the "R1" variant usually includes an onboard processor that performs: * **FFT (Fast Fourier Transform):** Converts time-domain signals into frequency-domain to determine distance. * **Clutter Rejection:** Filters out static objects or environmental noise. * **Decision Logic:** Provides a simple High/Low output on GPIO pins when motion is detected. --- ### 3. Pin Configuration (Typical) | Pin Name | Function | Description | | :--- | :--- | :--- | | **VCC** | Power | Positive supply (usually 3.3V or 5V). | | **GND** | Ground | Common ground reference. | | **TX** | UART Out | Transmits serial data (target distance/speed). | | **RX** | UART In | Receives configuration commands. | | **OUT** | Digital Out | High/Low signal triggered by detection. | --- ### 4. Comparison of Advantages * **Sensitivity:** Can detect minute movements (like breathing) or human presence even through thin non-metallic materials (plastic, drywall). * **Privacy:** Unlike cameras, it does not identify faces, making it ideal for smart home or washroom occupancy sensing. * **Reliability:** Not affected by temperature, light, or dust, which often interfere with PIR or Ultrasonic sensors. ---